Coral, we hardly knew ye: After only 200 million years of life, trace amounts of natural, harmless, invisible gas will allegedly kill 100% of the world's coral over the next 89 years

Coral reefs 'will be gone by end of the century' - Nature, Environment - The Independent

They will be the first entire ecosystem to be destroyed by human activity, says top UN scientist
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Coral reefs are on course to become the first ecosystem that human activity will eliminate entirely from the Earth, a leading United Nations scientist claims. He says this event will occur before the end of the present century, which means that there are children already born who will live to see a world without coral.

CO2 Science

In fact, the scleractinian corals, which are the major builders of the reefs of today, have been around some 200 million years, during most of which time both the atmosphere's CO2 concentration and its temperature were much greater than they are today, which should immediately raise a red flag about the proffered cause of the recent decline in reef growth.